It is instructive to inspect more closely the exactly-solvable kinetic equation approach[1]}, [2]}, [3]}, [4]} and try to understand why it fails in 2D case.
The starting point is the Fermi-liquid
transport equation
\(\frac{d f_1}{dt}+[f,H]=\sum _{21^{\prime }2^{\prime }}\left(w_{1^{\prime }2^{\prime }\rightarrow 12}-w_{12\rightarrow 1^{\prime }2^{\prime }}\right),\) 
